Mold for intraocular lens

ABSTRACT

The invention is a mold and method for using the mold to make a multi-stage intraocular lens. The mold is provided with a gate in fluid communication with a lens portion and/or haptic portion of the mold core. In addition, a gasket is provided around the mold core. As molding material is introduced into the mold via the gate, a vacuum is drawn around and through the gasket to evacuate air trapped in the mold core and to help pull the material through the mold core.

CROSS-REFERENCE TO RELATED APPLICATIONS

[0001] None.

STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT

[0002] Not Applicable.

APPENDIX

[0003] Not Applicable.

BACKGROUND OF THE INVENTION

[0004] 1. Field of the Invention

[0005] This invention relates generally to molds and, more particularly,to a mold for a multi-stage intraocular lens.

[0006] 2. Related Art

[0007] Multi-lens intraocular lenses have been disclosed in U.S. Pat.No. 6,488,708 B1 issued Dec. 3, 2002 (“the '708 patent”). Prior to theinvention disclosed by the '708 patent, lenses were only single stagelenses with haptics going from the lens to muscle tissue. The '708patent discloses multi-stage lenses that are stacked, with hapticstraversing between each lens, connecting each lens together.

[0008] While conceptually an excellent idea, there remains a need in theart to improve the manufacture of such intraocular lenses, such asproviding a mold and molding method for making such multi-stage lenses.

SUMMARY OF THE INVENTION

[0009] It is in view of the above problems that the present inventionwas developed. The invention is a mold and molding method for making amulti-stage intraocular lens. Specifically, the mold has a core withlens cavities, haptic cavities, and a gate in direct fluid communicationwith one or more of the cavities. In addition, the mold is provided witha gasket surrounding the core.

[0010] In use, molding material is flowed through the gate and into thecavities. As the silicone flows into the cavities, a vacuum is drawnaround the core and through the gasket. The vacuum evacuates air trappedin the mold core and helps pull the molding material through the moldcore.

[0011] Further features and advantages of the present invention, as wellas the structure and operation of various embodiments of the presentinvention, are described in detail below with reference to theaccompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

[0012] The accompanying drawings, which are incorporated in and form apart of the specification, illustrate the embodiments of the presentinvention and together with the description, serve to explain theprinciples of the invention. In the drawings:

[0013]FIG. 1 is a perspective view of a multi-stage lens produced by thepresent invention;

[0014]FIG. 2 is a perspective view of the mold, mold core, materialgate, and gasket of the present invention;

[0015]FIGS. 3A and 3B are top views of the mold core, illustrating theplacement of the gate;

[0016]FIG. 4 is a side view of the mold core;

[0017]FIGS. 5A and 5B are perspective views of the mold core sections;and

[0018]FIGS. 6A and 6B are partial cross-sectional views of the mold coreillustrated in FIGS. 3A and 3B, respectively.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0019] Referring to the accompanying drawings in which like referencenumbers indicate like elements, FIG. 1 illustrates a multi-stageintraocular lens, shown generally at 10, which is produced by thepresent invention. It is understood that lens 10 is shown with a pair oflenses, but that multi-stage lenses having more than two (2) lenses maybe produced by the method of the present invention. The multi-stage lens10 is provided with an anterior lens 12 and a posterior lens 14 that areconnected by a first haptic 16, second haptic 18 and third haptic 20.The multi-stage lens 10 is preferably made from silicone. The haptics16, 18, 20 are bendable, allowing the lenses 12, 14 to be adjustedrelative to each other. The haptics 16, 18, 20 can connect the lenses12, 14 at their periphery 22 or in their interior region 24.

[0020] Turning now to FIG. 2, a mold, shown generally at 26, has a moldcore 28, a material flow gate 30, and a gasket 32. The mold core 28 hasa pair of lens cavities 34, 36 that are in communication with each otherthrough haptic cavities 38, 40, 42. The gasket 32 surrounds the moldcore 28, including the lens cavities 34, 36 and the haptic cavities 38,40, 42. The material flow gate 30 is in communication with any one ofmore of the cavities in the mold core 28. Preferably, as illustrated inFIG. 3A, the material flow gate 30 is in communication with one moldcore cavity, such as one of the lens cavities 34, 36, and spaced apartfrom the haptic cavities 38, 40, 42. The material flow gate 30 can alsobe in communication with multiple mold core cavities, including thehaptic cavities 38, 40, 42. For example, as illustrated in FIG. 3B, thematerial flow gate 30 is in communication with one of the hapticcavities 38 as well as the lens cavity 36.

[0021] As illustrated in FIG. 4 and FIGS. 5A and 5B, the mold 26 can beformed by a pair of blocks 44, 46 that enclose a center block 48. FIG. 4illustrates a side view of the mold core 28 with the center block 48 inplace between the pair of blocks 44, 46. FIG. 5A illustrates the innerportion of the block 44 on one side of the mold 26, and FIG. 5Billustrates the inner portion of the block 46 on the opposite side ofthe mold 26 together with the center block 48. The center block ispreferably connected to a handle 50 that extends through the blocks 44,46. The handle 50 is equipped with offset pins 52 that guarantee theproper installation of the center block 48 into the mold 26, preventingthe accidental insertion in a backwards or upside down orientation.

[0022] These views of the mold 26 in FIGS. 4, 5A and 5B show aparticular embodiment of the mold core 28 in which exterior sides of thelens cavities 34, 36 are formed as recesses 54, 56 in the respectivepair of blocks 44, 46. The interior sides of the lens cavities 34, 36are enclosed by opposing sides 58, 60 of the center mold 48. Similarlythe exterior sides of the haptic cavities 38, 40, 42 are formed byhaptic recesses 62, 64, 66 in the pair of blocks 44, 46 while theirinterior sides are enclosed by the circumference 68 of the center mold.It will be appreciated that each one of the haptic recesses 62, 64, 66has complementary recessed portions 70, 70′ in the respective blocks 44,46. Accordingly, the haptic recesses 62, 64, 66 in each one of theblocks 44, 46 are formed from a pair of partial haptic recesses in theblocks 44, 46 (i.e., complementary recessed portions 70, 70′). Theinterface between the complementary recessed portions 70, 70′ should beidentical in number, position and shape to reduce the potential forflashing and/or discontinuities in the haptics 16, 18, 20 during themolding process. The blocks 44, 46 fit together snugly at theircomplementary faces 72, 72′ through hardware elements 74 that pull theblocks 44, 46 together. As particularly illustrated in FIG. 4, thematerial flow gate 30 is formed by a groove 76 in one of the blocks 44.

[0023]FIGS. 6A and 6B illustrate partial cross-sectional views of themold core 28 according to FIGS. 3A and 3B, respectively. The shape ofthe haptics 16, 18, 20 and connection to the lenses 12, 14 can bechanged through the use of different mold shapes. For example, thehaptic cavities 38, 40, 42 may be in communication with the periphery 78of a lens cavity 34 or an interior region 80 of a lens cavity 36.Similarly, the haptic cavities 38, 40, 42 could have an accordioncross-sectional shape 82.

[0024] In operation, the pair of blocks 44, 46 are locked in place whilethey enclose the center block 48. A molding material 84 is flowedthrough gate 30 into any one or more of the one mold core cavities.Then, a vacuum is applied to the mold core 28 through the gasket 42. Thevacuum evacuates the air from the mold core cavities and assists themolding material 84 in flowing through all of the mold core cavities inthe mold core 28.

[0025] In the preferred embodiment, the molding material 84 is siliconeand first flows from the gate 30 into one lens cavity 34 and then flowsinto the other lens cavity 36 through the haptic cavities 38, 40, 42. Itwill be appreciated that, in an alternative embodiment, a lens 86 (seeFIG. 6B) could be made out of a different material and placed in one orboth of the lens cavities 34, 36. The lens 86 would at least partiallyfill one or both of the lens cavities 34, 36, and the molding materialcould flow around a portion of the lens 86. For example, the lens 86could have attachment grooves or orifices where the molding materialwould lock into the lens 86. Such alternative lens materials couldinclude polymethylmethacrylate (PMMA), glass, and acrylics. Generally,the molding material can be any type of transparent, pliable material,like silicone and hydrogel. Other possible materials includehydroxyethylmethacrylate (HEMA) and polydimethyl siloxanes.

[0026] In view of the foregoing, it will be seen that the severaladvantages of the invention are achieved and attained. The embodimentswere chosen and described in order to best explain the principles of theinvention and its practical application to thereby enable others skilledin the art to best utilize the invention in various embodiments and withvarious modifications as are suited to the particular use contemplated.

[0027] As various modifications could be made in the constructions andmethods herein described and illustrated without departing from thescope of the invention, it is intended that all matter contained in theforegoing description or shown in the accompanying drawings shall beinterpreted as illustrative rather than limiting. For example, amulti-stage lens having three stacked lenses separated by three hapticsmay also be manufactured by the present invention. In such a case, thegate 30 can be placed in direct fluid communication with one lens cavity34. Then, material is flowed through gate 30 into the lens cavity 34. Asthe vacuum is applied through the gasket 32, material flows through eachof the haptic cavities 38, 40, 42, and into the connected lens cavities.Thus, the breadth and scope of the present invention should not belimited by any of the above-described exemplary embodiments, but shouldbe defined only in accordance with the following claims appended heretoand their equivalents.

What is claimed is:
 1. A mold core for a multi-stage intraocular lens,comprising: a plurality of lens cavities; a plurality of haptic cavitiesin communication with said lens cavities; and a material flow gate incommunication with at least one mold core cavity, wherein said moldcavity is selected from the group consisting of said lens cavities andsaid haptic cavities.
 2. The mold core according to claim 1, furthercomprising a gasket surrounding said lens cavities and said hapticcavities.
 3. The mold core according to claim 2, wherein said materialflow gate is in direct communication with at least one of said lenscavities.
 4. The mold core according to claim 2, wherein said materialflow gate is in direct communication with at least one of said hapticcavities.
 5. The mold core according to claim 2, wherein said materialflow gate is in direct communication with at least one of said lenscavities and at least one of said haptic cavities.
 6. The mold coreaccording to claim 2, wherein said haptic cavities are in communicationwith a periphery of said lens cavities.
 7. The mold core according toclaim 2, wherein said haptic cavities are in communication with aninterior portion of said lens cavities.
 8. The mold core according toclaim 2, wherein said haptic cavities have an accordion cross-sectionalshape.
 9. The mold core according to claim 2, further comprising a firstblock, a second block and a center block between said first block andsaid second block, wherein said first block has a first lens recess andsaid second block has a second lens recess and said first block and saidsecond block have a plurality of haptic recesses extending between saidfirst lens recess and said second lens recess, and wherein said centerblock encloses said first lens recess, said second lens recess and saidplurality of haptic recesses to form said plurality of lens cavities andsaid plurality of haptic cavities.
 10. The mold core according to claim9, further comprising a handle connected to said center block.
 11. Themold core according to claim 2, further comprising a flow of materialthrough said material flow gate and into said lens cavities and saidhaptic cavities.
 12. The mold core according to claim 11, furthercomprising a lens partially filling at least one of said lens cavities,wherein said lens is comprised of a material other than said flow ofmaterial.
 13. A mold core for a multi-stage intraocular lens,comprising: a first block having a face with a first lens recess and aplurality of partial haptic recesses extending between said first lensrecess and said face; a second block having a second lens recess and acomplementary face with a shape corresponding to said face of said firstblock and a plurality of complementary haptic recesses corresponding innumber, position and shape to said partial haptic recesses of said firstblock, wherein said complementary haptic recesses extend between saidsecond lens recess and said complementary face; a center block betweensaid first block and said second block, wherein said center blockencloses said first lens recess, said second lens recess and said hapticrecesses to form a plurality of lens cavities and a plurality of hapticcavities extending between said plurality of lens cavities; a materialflow gate in communication at least one mold core cavity, wherein saidmold cavity is selected from the group consisting of said lens cavitiesand said haptic cavities; and a gasket surrounding said first block andsaid second block.
 14. The mold core according to claim 13 wherein saidmaterial flow gate is further comprised of a groove in said face of saidfirst block.
 15. The mold core according to claim 13, further comprisinga handle connected to said center block.
 16. The mold core according toclaim 13, further comprising a flow of material through said materialflow gate and into said lens cavities and said haptic cavities.
 17. Themold core according to claim 11, further comprising a lens partiallyfilling at least one of said lens cavities, wherein said lens iscomprised of a material other than said flow of material.
 18. A methodfor a making multi-stage intraocular lens, comprising: providing a moldcore, wherein said mold core comprises a plurality of lens cavities, aplurality of haptic cavities in communication with said lens cavities,and a material flow gate in communication with at least one mold corecavity, wherein said mold cavity is selected from the group consistingof said lens cavities and said haptic cavities; providing a gasketaround and said mold core; flowing a material through said material flowgate and into said cavities; and applying a vacuum through said gasket.19. The method according to claim 18, further comprising the step ofenclosing a center block between a first block and a second block,wherein said first block has a face with a first lens recess and aplurality of partial haptic recesses extending between said first lensrecess and said face, wherein said second block has a second lens recessand a complementary face with a shape corresponding to said face of saidfirst block and a plurality of complementary haptic recessescorresponding in number, position and shape to said partial hapticrecesses of said first block, said complementary haptic recessesextending between said second lens recess and said complementary face,and wherein said center block encloses said first lens recess, saidsecond lens recess and said haptic recesses to form the lens cavitiesand the haptic cavities.
 20. The method according to claim 18, furthercomprising the step of placing a lens in at least one of the lenscavities before flowing said material through said material flow gateand into said cavities.